Look at Williams for a Firesight, FP-94/36, Lyman for a peep sight or peep and post combo. Lyman also has a tang sight, but I wouldn't recommend it. On my 336CS, it sits too close to my face. Cost me $200 in custom made polarized prescription lenses when the recoil tried to shove the sight into my eye.
At that point, I went with a Lyman that mounts on the side via the drilled and tapped holes. I also believe that there is a firm (XS Sights, something like that) that makes a ghost ring sight to mount on the top of the receiver, using the holes drilled and tapped for the scope.
You can find these on-line at Cabelas, Midsouth Shooter's Supply (probably the cheapest), or Midway USA.
One thing, you might have to change the height of your front sight. I was lucky and didn't have to, but every firearm (and shooter) is different.
Last year, I switched my Lyman Peep over to a Williams peep with the Firesight. Because of health problems, I haven't had a chance to shoot it yet. If you could , let me know what you decide on and how well it works out. Good luck.